Replying to Binding help!

Hey guys, sorry if this seems like a stupid question.

I just got my Armada Halo 2's mounted at -5 from true center (factory recomended) and I'm thinking that's a bit to far back. I could be wrong though. I want to ski about 35% park and 65% all mtn/powder. The bindings that I have on the skis can be slid to fit bigger boot sizes and I was wondering if I could slide them up a bit without messing up my whole setup.

Any help would be appreciated!

Thanks